This invention relates to a sheet feeder for use with a printing device for printing a stack of sheets already bound along a common edge.
There are times when it becomes necessary to print onto a stack of sheets that have already been bound together along one edge in a book-like or pamphlet form. Take, for example, the case of annual calendars of the type sold to businesses who wish to distribute them for advertising purposes. The suppliers of such calendars often print up and bind together the individual monthly calendars, leaving space on the sheets for advertisements to be printed. Once the calendar manufacturer knows which ads to print onto the spaces provided on the individual calendar sheets, each sheet must be turned over individually and fed to a printing press to print the ad, which in a manual operation is a time-consuming and tiresome job.
The object of the invention therefore is to provide an automated, fully mechanized sheet feeder for performing such printing work, i.e., which is able individually to lift the individual sheets of a stack bound to one another on one edge (of a stitched or otherwise bound pad or the like), feed them to the printing device and turn them over in the course of this operation.